Wenger expects Wilshere to return in “late February or early March” and insists the midfielder can still fulfil his potential despite undergoing multiple operations on his ankles in recent years.

“He’s very down,” said Wenger. “Jack is a football man who loves the game. But on the other hand, he's a very strong character as well and he has learnt to deal with adversity at a very young age.

“He always came out stronger and when I spoke with him, the final sprint of the season is already in his mind and [he wants] to come back stronger. He's a very strong boy.

“I haven’t spoken to him before the surgery but I did before. We knew on Wednesday night that he would have surgery certainly on Thursday. He’s prepared and focused to come back and finish the season well.

“I think he will be back at the end of February, beginning of March and he will focus on coming back to rehab, having a strong rehab, and then I’m sure he will help us to do well until the end of the season.

“Our first quality in our job is health. If he has no problem with his joints, he will make a massive career. I was more worried one year ago than I am today because he had two or three surgeries on his right ankle. At some stage, you could raise that question but today I am much more confident that he will [fulfil his potential].”

Five things we learnt from Arsenal v Borussia Dortmund

Five things we learnt from Arsenal v Borussia Dortmund

1/5
Yaya Sanogo scores when he wants

Well, according to Arsenal fans anyway. The 22-year-old French forward finally scored his first goal for the club and maybe showed why Arsene Wenger has put his faith in him. Sanogo, who started in attack with Olivier Giroud ineligible and was a handful until he came off injured late on, had failed to find the net in 19 games for Arsenal before tonight. This was his first club goal since he scored for Auxerre against Toulouse in November 2011. Sanogo took his goal well after playing a neat one-two with Santi Cazorla. Well worth the wait.

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2/5
Jurgen Klopp looked comfortable at Emirates Stadium

Some saw this as an opportunity for Klopp to impress the Arsenal hierarchy and, if anyone wanted to keep an eye on the Borussia Dortmund boss, they got a good look at him. Klopp stood on the edge of his technical area barking instructions at his players for the full 90 minutes. Klopp says he could see himself managing an English club and he is frontrunner with the bookmakers to succeed Arsene Wenger. Whether he is the right man for Arsenal remains up for debate.

3/5
Tough tests lie ahead

Arsenal have now reached the knockout phase for 15 years in a row. Their record of progressing through the group stage is remarkable, especially when you consider Manchester City’s struggles in Europe. But, barring a Dortmund slip-up against Anderlecht in the final round of Group D fixtures, a failure to progress as group winners means the Gunners will face a European heavyweight in the next round. On current standings, Arsenal could face Atletico Madrid, Real Madrid, Bayern Munich, Paris St-Germain, Porto or Bayer Leverkusen

4/5
Arsenal still look too open

Despite keeping a clean sheet, the Gunners looked far from solid at the back during the first half. Laurent Koscielny was on the bench and his return will be a huge boost for Arsene Wenger. But there were still signs that Arsenal do not know when to keep things tight. They only needed a point to go through and, after going 1-0 up after 73 seconds, continued to pile forward, leaving themselves exposed at the back.

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5/5
Alexis Sanchez shows no signs of slowing down

Sanchez has scored seven goals in his last five games. Ian Wright said this week that Arsenal are a "mid-table team" without the Chile star and he again showed his class with a brilliant curling effort to seal the win. Does he score scrappy goals? Sanchez was Arsenal's brightest player and Arsene Wenger will hope he can maintain this fine form over the busy festive period.

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Wilshere’s injury will not force Wenger into the January transfer market, although the Frenchman admitted he will “try to get at least one body in” when the window opens at the beginning of 2015.

Wenger distanced the club from a move for goalkeeper Petr Cech and dismissed suggestions Wolfsburg have made an enquiry for unsettled forward Lukas Podolski.

Arsenal face West Brom at the Hawthorns in tomorrow’s lunchtime kick-off with several players carrying knocks following Tuesday’s Champions League win against Borussia Dortmund.

Goalkeeper Wojciech Szczesny has not trained due to a hip injury, Yaya Sanogo is a doubt with a hamstring injury but Mikel Arteta is definitely sidelined with a calf problem.

Danny Welbeck has a fitness test today on knee and hamstring injuries while Theo Walcott is out for the next two games with an inflamed groin aggravated during training with England.

Mathieu Debuchy is still two weeks away from a return following his own ankle surgery while David Ospina should be available in a similar timeframe as he bids to recover from a thigh injury.

“I don't complain with the injury situation, we deal with it,” said Wenger. “It is part of my job to deal with it. We played in the qualifiers of the Champions League, and had players who were at the World Cup, there was a big demand on physical quantity of work, and maybe we paid a bit of a price for that.”